Signs of the Cast Shadow Master

By Art Gallery of New South Wales

The head and shoulders of a bearded man in feathered hat and fur-trimmed clothes. Over his left shoulder is a darker shadow on a green background. — A detail of the Gallery’s Henry VIII painting after conservation treatment in which the original cast shadow has been revealed

Mystery surrounds the Art Gallery of NSW’s portrait of Henry VIII as we’ve been exploring in recent posts.

To get closer to the truth – and to help us plan its much-needed conservation treatment – we needed to get much, much closer to the painting itself.

We started with conventional imaging techniques – X-radiography, infrared reflectography and ultraviolet fluorescence – undertaken at the Gallery, which suggested there had been damage to the painting. This included a break in the panel through the centre, the addition of an extra panel piece along the right edge and extensive overpainting by previous restorers.

At the University of NSW’s LUXLAB imaging laboratory, the portrait was scanned at 1200 dpi, before and after cleaning, giving a microscopic view of the entire painting surface. This revealed cracks, losses, brush marks and traces of paint invisible to the naked eye, enabling a more precise comparison between our painting and similar ones in London.

We observed the same distinctive ‘dab-and-twist’ technique for the ruff of the shirt collar, characteristic fine decorative and calligraphic brushwork, and some minute marks that could only have been carried out under magnification, indicating the hand of a miniaturist.

The same ‘dab-and-twist’ technique for the ruff can be seen in the National Portrait Gallery’s Henry VIII painting (left) and the Art Gallery of NSW’s work (right).

Examples of the precise calligraphic and decorative brushwork in the Gallery’s painting

The next stop was the Australian Synchrotron in Melbourne, which produced a series of data-rich maps of our Henry over the course of 23 hours using the X-ray fluorescence microscopy beamline.

Copper, gold, mercury, iron, lead … each element produces a unique fluorescence signal when appropriately illuminated by X-rays, and as these correspond with particular pigments, we now had a picture of the exact location of all the materials comprising the painting.

The painting mounted on the X-ray fluorescence (XRF) beamline at the Australian Synchotron

Among the many discoveries was one particularly significant revelation: evidence of the cast shadow that had seemed to be missing from our portrait. This now placed the artwork firmly in the same group of Henry portraits as those in London’s National Portrait Gallery and Society of Antiquaries, which, in the absence of a named artist, had at one time been ascribed to the enigmatically titled Cast Shadow Master, so called because the portraits included a shadow cast by the sitter.

The key to this discovery was in the greens.

We could now distinguish between the original greens (created using a patina that results from mixing vinegar and copper) and a chrome green that must have been added much later (chrome was not discovered until 1800).

In the conservation treatment that followed, the non-original paint was removed, revealing a shadow cast from Henry’s head onto the background to the right – a shadow that was present in all the other portraits of the Tudor group in London.

Left to right: a detail of the painting before conservation treatment with a red line to indicate the chrome green overpaint on the right, part of the copper XRF map of the same section, and a detail of the painting after removal of overpaint revealing the original shadow and added panel

This also made sense of a dark green strip on the portrait’s left edge, which is intended to suggest a shadow cast by the frame. An illusion is created of a recessed space in which Henry appears to sit, hands resting on a cushion, as though present and looking into the room. The cushion itself, which was painted black, also appeared to have been painted green originally.

For the first time we could see that the sleeve at the lower left appeared to be a slashed sleeve with the white shirt undergarment pulled through the decorative cuts in the upper garment – another shared characteristic of the Henry group to which our painting belongs. This too had been obscured by a restorer’s overpaint, which we subsequently removed.

Gold leaf was visible for the first time in exquisite detail. By zooming in, we can see the fine creases called lamellae, caused by the hammering action when the gold leaf was manufactured, probably by beating out gold coins. The fine sheets have been laid in place by the artist in a technique similar to that used in illuminated manuscripts and in religious icons and European paintings from the 15th century.

Left to right: a detail of the lower left sleeve before conservation treatment, part of the gold XRF map showing the use of gold leaf, and a detail of the painting after treatment in which the original slashed and gold leaf sleeve has been revealed

Elsewhere, the mercury map (indicating vermilion, a bright red paint) revealed that one of Henry’s fingers had been straightened during a restoration. This overpainting too has since been removed and the original curved finger can be seen again.

Left to right: a detail of the right hand before conservation treatment, part of the mercury XRF map, and a detail of the painting after the removal of overpaint in which the original position of the finger has been revealed

You can explore the elemental maps and other aspects of the project in our slideshow.

Distributions of mercury (red), iron (green) and gold (blue) measured at the Australian Synchrotron, part of the Australian Nuclear Science and Technology Organisation. Image courtesy Dr Daryl Howard.

The synchrotron mercury distribution map shows the vermilion paint (mercury sulphide). You can see where it has been mixed in with other colours to intensify the redness of the paint mixtures. Image courtesy Dr Daryl Howard.

The synchrotron iron distribution map shows the presence of the naturally occurring brown mineral pigment iron ochre. Note the change in the position of the neckline on the right. Image courtesy Dr Daryl Howard.

The synchrotron gold distribution map images, for the first time, the sheets of gold leaf applied prior to painting and a faint trace of the shell-gold decorated border of the jacket. Image courtesy Dr Daryl Howard.

The synchrotron copper distribution map shows that the green pigment verdigris was used to paint the background and the original cushion. The remnant of the 'lost' cast shadow of Henry's head can be seen on the right. Image courtesy Dr Daryl Howard.

The synchrotron chromium distribution map shows the location of the non-original green pigment, which where it had been painted over the original cast shadow. Image courtesy Dr Daryl Howard.

The synchrotron lead distribution map shows the lead white paint, including the lead priming. Image courtesy Dr Daryl Howard.

The synchrotron lead distribution map provides a much clearer image of the location of the lead white paint than here, where the X-rays are also blocked by the thickness of the panel and other materials.

The infrared image which reveals the limited use of underdrawing.

The ultraviolet image showing the greenish fluorescing aged natural resin varnish. You can also see the characteristic salmon-pink fluorescence of the natural rose madder paint used for the tunic.

Fine decorative work, over gold leaf, seen under the microscope.

Damaged lower edge showing the layer structure: wood, priming, original green cushion, followed by non-original overlayers.

Remnant of the shell (powdered) gold, used for decorative hatching on the jacket, seen under the microscope.

The panel itself was also holding secrets, but to unlock those we needed a dendrochronologist – a story we’ll investigate in our next Henry VIII post.

The Gallery’s Henry VIII portrait is on display from 12 May to 9 September 2018 in Henry VR.

The conservation treatment project that sparked this research was supported by the Conservation Benefactors, most notably Dorothy R Spry (in memory of), Hamish Parker, Leonard Groat and Kenneth Reed AM.